1. Field of the Invention
The present invention relates generally to improvements in bumpers for automotive vehicles and, more particularly, but not by way of limitation, to improvements in bumpers for ambulances.
2. Brief Description of the Prior Art
It has become common practice in recent years to construct ambulances by mounting a patient compartment, constructed of sheet metal, on rear portions of the frame of a truck body with forward portions of the frame supporting the usual truck cab. As supplied by the manufacturer, the rear bumper of such an ambulance usually consists of little more than a crossbar, constructed of a length of rectangular tubing, that is welded in its medial portions to the frame of the truck body and has end portions that extend laterally from opposite sides of the frame.
It has been found in practice that such bumpers do not adequately protect the patient compartment from damage occasioned by rear-end collisions to which an ambulance might be subjected and, moreover, such bumpers can be subjected to damage through mishaps that occur in the normal usage of an ambulance. For example, the end portions of a length of rectangular tubing serving as a bumper extend in cantilever fashion from the frame of the ambulance so that a collision that occurs off center of the rear of the ambulance can bend the end portion of the bumper about the connection of the bumper to the ambulance frame with the result that the vehicle colliding with the ambulance can engage the patient compartment of the ambulance causing heavy damage to such compartment. Similarly, it may often be necessary for an ambulance to cross a medial strip in a freeway or highway so that the rectangular cross section of the rear bumper can result in snagging of the ends of the bumper with the ground or with obstructions in the medial strip of the freeway to occasion damage to the rear bumper. Because of these defects, high maintenance costs have been associated with the upkeep of ambulances provided with conventional bumpers.
While the maintenance costs associated with the upkeep of an ambulance can, to some extent, be reduced by attaching braces between the end portions of the conventional bumpers and the frame of the ambulance, it has been found that such braces do not really solve the problem. Tips of the end portions can still be bent to permit a second vehicle to collide with the patient compartment of the ambulance and the rectangular cross section of the conventional bumper, even with bracing, will still permit snagging of the bumper should the ambulance cross a medial strip of a freeway with the result that merely bracing the rear bumper of the ambulance has proven to be generally ineffective in providing a significant reduction of maintenance costs for the ambulance.
It is also known to weld a reinforcing member; for example, a length of oil field drill pipe, to the rear bumper of a commercial vehicle but such solution to the maintenance problems associated with ambulances is defective in several respects. In addition to providing the ambulance with an unsightly appearance, the cost of the drill pipe is by no means insignificant.